This application claims the priority of Korean Patent Application No. 2002-81380, filed on Dec. 18, 2002, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a digital broadcast system, and more particularly, to a digital broadcast system that receives digital broadcast services on a passive optical network (PON).
2. Description of the Related Art
FIG. 1 is a diagram illustrating a cable TV network 101. The cable TV network 101 is generally used for providing cable TV programs through a cable TV 111 and a cable TV converter 121. However, as shown in FIG. 1, a variety of devices, including a telephone device 112, a telephone terminal 122, a cable router 113, a cable modem 123, a video-on-demand (VOD) server 114, a VOD converter 124, a high availability (HA) server 115, and an HA terminal 125, can be further connected to the cable TV network 101 so as to provide various services, such as Internet services, VOD services, and telephone services and thus make the utmost use of a broad bandwidth provided by the cable TV network 101.
So far, a variety of high-speed Internet services have been provided using either a technique of accessing the Internet with the help of such a conventional cable TV network as the one shown in FIG. 1 or a technique of providing Internet services to predetermined dense areas in terms of the number of users by using an internet network. The former technique, however, has disadvantages in terms of providing data services. On the contrary, the latter technique has disadvantages in terms of providing broadcast services. Therefore, a brand-new digital broadcast technique, which can successfully provide digital broadcast services using a conventional network and can also provide data services of good quality to uses, is necessary.